Talking-machine record



July 2, 1929- N. REDDIE E1 AL TALKING HACHINE RECORD Filed Nov. 18, 1925Patented July 2, 1929.

UNITED STATES v 1,719,339 PATENT OFFICE.

LOVELIa NEWTON REDDIE OF LONDON, ANI) BRENCHLEY ERNEST GEORGE MITTELL,0F IVER, ENGLAND, ASSIGNORS TO VICTOR TALKING MACHINE COMPANY, OFCAMDEN, NEW JERSEY, A CORPORATION OF NEW JERSEY.

TALKTNG MAGHINE RECORD.

Application filed November 18, 1925, Serial No. 69,847, and in GreatBritain December 24, 1924.

This invention relates to improvements in and relating to talkingmachine records.

It is known that a record upon a wax cylinder gives in some respects amore faithful reproduction of the recorded sounds than a record out upona disc, and the proposal has been made to record sounds upon a'waxcylinder, by the usual or any known method,

and to transfer the record so obtained from the c linder to a disc. Ithas been proposedto e eat this transfer operation by mechanical meanssuch as a lever, one end of which traces in the sound line out on thewax cylinder whilst the other end of the lever is furnished with acutting tool whereby a record is cut in a wax disc. From the wax disc amatrix is made in the usual or any suitable way and from the matrix anumber of recordscan be pressed.

In this transferring operationit has been proposed not only to transferan up and down out from a cylinder and to obtain an up and down out on adisc, but it has been proposed also to convert the up and down out onthe cylinder into a lateral cut of uniform depth on the disc.

There are certain difiiculties in performing this mechanical transferingoperation. It is desirable that the tracing point and the recording toolshould both rest quite lightly on the surfaces with which theyrespectlvely cooperate and it is diflicult to arrange a cylinder and adisc sufficiently closeto one another to enable the transferringmechanism to be sufliciently light and at the same time sufficientlyrigid. The movements of the tracing point and cutting point arenecessarily very rapid, where sounds of high frequency are beingtransferred, and this is ill true even thou h in the transferringoperation the cylinder and disc are rotated at much lower speeds thanthose at which the cylinder was first recorded and the disc record willbe played. If the transferring mechanism possesses any considerablemass,

4 it will be understood that these rapid movements result in the tracingpoint and recording tool respectively performing movements which do notaccurately correspond to the sound record cut onthe wax cylinder. If inthe transferring operation an up and down out on the cylinder has to beconverted into a lateral'cut on the disc the difficulties as referred toabove are increased.

is of the well One of the objects of the present inventlon is to removethese difficulties in the operation of transferring from one recordedsurface to another.

According to the present invention, in the transformation of a soundrecord of one knid into a sound record of a different kind, the soundafter being recorded is converted into electrical oscillations which areadapted to operate a recording device.

Further, according to.the present invention' a sound record of any kindmay be transferred to a sound record cut in a solid body, that is tosay.a record adapted to be reproduced. by mechanical means, byconverting the first sound record into electrical oscillations which arecaused tocut the rec- 0rd in the solid body.

Means may mg the electrical oscillations either to-accentuate or todiminish certain ranges of frequency or to alter the amplitude of thewhole, and to permit'of the adjustment of these controlling means areproducer or loud speaker may be connected in such a manner as toreproduce the electrical oscillations in the form in which they arebeing recorded.

One method of carrying out the invention will now be described, by wayof example, with reference to the accompanying drawmg in which is showndiagrammatically a method of transferring a sound record, of either upand down or lateral cut type, from a cylinder to form'a record, ofeither up and down or lateral cut type, upon a disc.

A reproducing stylus a traces lightly in and is oscillated by the soundline upon the rotating cylinder 6 and thereby generates feebleoscillating currents in the primary 0 of the input transformer d. Thereproducing device e may be of any known or suitable form. Theoscillating electromotive forces set up in the secondary f of thetransformer d are impressed upon the grid circuit of a thermionic valvewhich is the first valve of an amplifier which may comprise any desirednumber, of valves although, in the present example, three are shown..The intervalve coupliiiggillustratecl known resistance-capacity type.The oscillating currentsfrom the last amplifying valve b arepassed'through the primary 6 of an output transformer j and currentsgenerated in the secondary k of this also be provided formodifytransformer pass to the recording device Z,

lines as the reproducing device 6. The

stylus m of the recording device 1 cuts a record upon the rotating discat. i

Control of the volume and quality of the sound transmitted is obtainedby the following means: The primary 0 and the secondary f of the inputtransformer (13 are made so that their inductances are variable eitherby means of suitable tappings or otherwise and a variable condenser 0 isconnected in parallel with the secondary k of the output transformer j.Adjustment of each of these three controlling means will alter both theamplitude and the wave form of the electrical oscillations but in themain it may be said that adjustment of the primary c and of thecondenser 0 serves to control the wave form of the oscillations whilstadjustment of the secondary f mainly affects the amplitude of theoscillations since the currents flowing in the grid circuit are onlythose due to inter-electrode capacity and are consequently very smallcompared with the currents flowing in the circuits of the reproducingdevice 6 and of the recording device Z. In order that the operator maybe able to listen to the sounds in the form in which they are beingrecorded and so make any necessary adjustments during the process oftransference, a loud speaker p is provided and is connected across asmall portion of a resistance 9 which is shunted across the secondary kof the output transformer j, the currents required to operate therecording device I being in general much greater than those required tooperate the loud speaker satisfactorily.

The record upon the cylinder may be made b the direct action of soundwaves upon a diaphragm connected with the recording tool or the soundwaves may be allowed to strike a microphone, or equivalent means forconverting sound oscillations into electrical oscillations, and toproduce electrical oscillations in a circuit containing a suitablethermionic amplifier, the amplified oscillations being used to operatean electrical recording device, or the record on the'cylinder ma beproduced in any other known or suitab e manner.

The tracin point and also the recording tool used in t e transferringprocess may be made very light and the transferring may take place at aspeed considerably lower than that at which the record was originally Ymade so that the movement of the oscillating parts can be made tocorrespond very accurately with the sound record cut on the cylinder. Inorder to still further reduce the possibilities of distortion due to theinertia of moving parts a record may first be made by anyknown process,such as that employing a cathode ray oscillograph device, in

which all oscillating parts are substantially inertia-free and thisrecord may then be transferred by the method according to the presentinvention, at a reduced speed, to a record which is in the mostconvenient form for reproduction. In the case of the production of a waxrecord, the speed may be adjusted so thatsubstantially no distortion isintroduced owing to the mass of the oscillating stylus and the mostsuitable cutting speed for the wax may also be taken into consideration.

The present invention, therefore, is not confined to the operating oftransferring a sound record from a wax cylinder to a disc. Sound recordsare well known in the form offilms, for example, on which a photographicrecord is made, a beam of light which falls on the film being moved, orits intensity being varied, by and in accordance with sound waves, orthe photographic sound record may be produced by a cathode rayoscillograph device. From these photographic records, sound has beenreproduced in a variety of ways, as for example b passing light throughthem, whilst in motion, on to a light-sensitive cell, from which avariable current is derived, and this current, after amplification bymeans of thermionic valves for example, is used to actuate a loudspeaking telephone; or the photographic film may be used to provide avariable capacity, to vary an electric current in accordance with thesound waves recorded.

Sound records are also known which are recorded by effecting thevariable magnetization of metal bodies such as wire, metal ribbons, ormetal discs, and from these records variable electric currents arederived by suitable means which, after amplification by thermionicvalves, actuate a loud speaking telephone.

Sound records in the form of films, ribbons or wire are not easilyhandled, and the apparatus for reproducing therefrom is of a delicateand highly technical nature and 110% 1of a kind suitable for use by thegeneral pu 1c.

The present invention may be applied to the purpose of obtaining, fromsound records of the above mentioned type, or frpm whatever type ofrecord constitutes an" accurate and faithful record of the soundswhich-it is i desired to reproduce, electrical currents or,

current impulses' which after amplification by thermionic valves, areused to operate a recording tool to cut a record in a body of a.convenient form for handling, such as a cylinder or disc, which gorduplicates of which) can be reproduce with a talking machine, that is tosay, can be reproduced by mechanical means.

A further application of the present invention is in the preparation ofa new wax blank from an existing talking machine matria or record. Thereare matrices which have been in existence for several years and possessconsiderable historical and musical value, but may have someimperfections due possibly to the less perfect recording method in usewhen they Were made. A suitably formed tracing point can be made totrack on these matrices, or on a record made therefrom, the currentsthereby produed are am,- plified as above described and anew Wax blankis cut. During the transferring process the amplification of anyimperfect passages can be modified, as for example by reducing theamplification of a passage that is too loud, by increasing momentarilythe resistance in some part of the circuit, or the quality of certainpassages can be altered (e. g. to bring out the overtones) by using avariable condenser in series in the circuit to or from the amplifier,the overtones being emphasized by reducing the capacity.

lFVe claim:

1. The method of transforming a mechanically recorded sound record intoan electromechanically recorded sound record which consists in employingthe sound record to be transformed for producing mechanical vibrations,converting said vibrations into feeble oscillating currents in anelectrical circuit, audibly reproducing said currents, variablycontrolling both the amplitude and the Wave form of said currentsaccording to the audible reproduction to render the same more pleasing,transferring the currents so a controlled into mechanical vibrations,and

recording said mechanical vibrations on the other record ltatent I la.lfillhdd h lt la herehr eertilied that error anaem a in ahove nurnhererlpatent requiring retraction as follows: 2, atrihe out the word "by";same page, line 61, claim caarrrrea'ra or GORREGTION WWN REDDIE ET AL.

2. The method of transferring sound mechanically recorded on by a soundrecord onto a recording surface which consists in moving said soundrecord at a speed considerably lower than that at which said soundrecord Was originally made, employing said slowly moving record forproducing feeble oscillating currents in an electric circuit, audiblyreproducing said currents, variably controlling both the amplitude andwave form of said currents according to the audi ble reproduction torender the same more pleasing, and transferring the currents socontrolled onto said recording surface.

3. The method of transferring a sound record from a cylinder onto a diskwhich consists in moving said cylinder at a speed considerably lowerthan that at which said sound record Was originally made, employing thesound record to be transferred for producing mechanical vibrations,converting said vibrations into feeble oscillating currents in anelectrical circuit, audibly reproducing said currents variablycontrolling both the amplitude and Wave form of said currents accordingto the audible reproduction to render the same more pleasing, transferring the currents so controlled into me-v chanical vibrations andrecording said mechanical vibrations on said disk.

In testimony whereof, We have signed our names to this specification atLondon, England, this third and fourth days of November, 1925,respectively.

LOVELL NEWTON REDDIE. BRKENCHLEY ERNEST GEORGE MITTELL.

Granted my 2, 1929, to

the printed specification of the Page 3, line 39, claim 3, after theword "currents" iuaert a comma; and that the said Letters Patent shouldbe read with corrections thereia that the same we in. the Patentlhllice,

y conform to the record of the case 7 hianerl hurl aealerl this llithray of hotelier, A, l) I M, J. Moore, hating Commissioner of Patents.

